There are two types of libraries you can use to send HTTP messages; clients and adapters. A client implements the
HttpClient and/or the HttpAsyncClient interfaces directly. A client adapter is a class implementing the
interface and forwarding the calls to an HTTP client not implementing the interface. (See Adapter pattern on Wikipedia).

Note

All clients and adapters comply with Liskov substitution principle which means that you can easily change one
for another without any side effects.

There is no library registered with those names. However, all client implementations (including client adapters) for
HTTPlug use the provide section to tell composer that they do provide the client-implementation.